Engineering (Apocalypse)

Engineering is the discipline of 'making stuff'.

Engineering Workshop Facility

The workshop is available as a Small facility in the beginning, and when the relevent research is completed, a Large facility will be an option. Placing small or large workshops would be ideally spread across all bases to limit the possibilty of losing all manufacturing capability if built only in one base.

Manufacturing

A compact workshop base layout ...which will wipe out all manufacturing capability if it were to be lost.

These is nothing to built at the start!
X-Com will need to build more facilities in the future to enable the manufacture of advanced weapons, crafts and devices, armors, etc. Constructing an item will allow a profit to be made when sold on the market.

Optimising production allows larger profits!

Completion And Timing

The timing to finish any project is always completed on the hour.

Multiple small items of the same type built over a multiple day production run, will efficiently use workshop space and engineer skill instead of short stop-start projects.
Maximum quantity in any project is 50. The slider can be moved at anytime to increase or decreased this amount, up to the limit.
A project started within the current hour, will be calculated as if it started from the beginning (of this hour).

eg: a project started at 0:59 and needing one hour to build three items, will complete the project in one minute! ...because always completed on the hour. (see Build Time‡ below)

Building something that can be recovered from a mission may not be the best use of the workshop. If nothing is needed to be built, build anything that gives the best profits.
An idle workshop is wasting money! Get your money's worth!

Cancel A Project

If needing to start a new project as soon as possible and there is a large project already in progress, it is best to not outright cancel it, but to move the slider to have no more remaining items in the build queue and then allow this product to finish. If cancelled, the progress made with this last item will be lost, including any costs.

Massive projects, usually taking many days for just one item and should be planned so that it is not cancelled.
If a project will still take many hours to complete with no more items remaining in the quantity queue, the decision to cancel (usually something big and expensive) may be an unacceptable waste of funds.
Time is money!

Overheads

or, Costs Of Upkeep
Engineers receive a salary and maintenance of facilities (living and workshop) which will reduce your profits by a certain amount each and every week. Once a project's profit is calculated without interuption (preferably over a whole week), it is then matched with the size of the facility being used. Profit totals will become more accurate:

Small Workshop costs = 250

Living quarters is half filled, so maintenance can be halved as well.

Large Workshop costs = 500
An idle workshop is inefficient! Make something even if it is barely profitable!

Flooding The Market

Every item is profitable to manufacture, but your sell price (and eventual profit) is determined by market forces. If you are selling so much (ie: flooding) that you drive the price down in the proceeding weeks, you will have to re-evaluate each manufacturing run using this new sell price of the new week, to find the best profits.

Items recovered or built-in-bulk may be hoarded until the sell price rises if storage space is of no concern.

Items have differing amounts in the Market Capacity column which is a rough indicator of how many you can sell before you influence the Sell Price towards its lowest value.
eg: selling x25 Dimension Missiles may slightly reduce the new-week sell price, but selling x25 Disruptor Guns will be classed as 'flooding' and will drive the sell price down, faster with a 'flood' every consecutive new week.

An idle workshop is not making money! Swap manufacturing projects every week to avoid flooding the market with a single item.

Chart Definitions And Formulae

Note: Advanced Workshop = Large
Small Workshop = 500 total skill, maintenance 250 per week.
Large Workshop = 1000 total skill, maintenance 500 per week.

Manufacture Item: no know = no no.
Build Cost: Internal cost to build one item.
Build Time‡: Internal time to build one item if spanning multiple hours.

Build Time H: Produce one unit in amount of hours (unrounded), based on Facility.

Build Time H = {Build Time ÷ Facility}

Facility: Small (500) or Large (1000). Using Large to build Small items allows double production quantity and profit.
Market Capacity: how much to sell before price starts to gets affected at the end of the week, every week.
Sell Price: typical of the market.
Raw Profit: sell one of something to get this amount of credit-dollars (disregarding maintenance costs or time taken to build).

Profit Per Build Time: portion of a credit-dollar you get for each tick of the build clock (Facility irrelevant, not based on hours).

Profit Per Build Time = {Raw Profits ÷ Build Time}

Profit Per Hour: $$$.¢¢ money per hour dependant on Facility

Profit Per Hour = {Raw Profits ÷ Build Time H}

Quantity Per Week: un-interrupted production in a full and exact one week, 168hours (disregarding maintenance).

Quantity Per Week = {168 ÷ Build Time H}

Profit Per Week: comparison of a total week production run which will depend of maintenance which is not included.

Profit Per Week = {Quantity Per Week × Raw Profit}

Manufacture Item	Build Time	Facility	Build Time H¹	Build Cost	Sell Price	Raw Profit²	Profit Per Build Time³	Market Capacity	Profit Per Hour³	Quantity Per Week†	Profit Per Week³
Bio-Transport Module	4000	small	8	750	950	250	0.0625	4	31.25	21	5250
Boomeroid	3000	small	6	230	840	610	0.2033↓	15	101.67	28	17080
Vortex Mine	5000	small	10	250	1130	880	0.176	25	88	16.8	14784
Disruptor Gun	7000	small	14	600	2100	1500	0.2143↓	10	107.14	12	18000
Devastator Cannon	12000	small	24	1200	4500	3300	0.275	20	137.5	7	23100
Dimension Missile Launcher	5500	small	11	1200	3100	1900	0.3455↓	25	172.72	15.27	39018
Dimension Missile	4000	small	8	400	1300	900	0.225	30	112.5	21	18900
Personal Disruptor Shield	14000	small	28	2000	5770	3770	0.2693↓	30	134.64	6	22620
Personal Cloaking Field	18000	small	36	3000	8300	5300	0.2944↓	30	147.22	4.667	24733
Personal Teleporter	25000	small	50	6000	18200	12200	0.488	40	244	3.36	40992
Toxigun	3000	small	6	1200	2780	1580	0.5267↓	8	263.33	28	44240
Toxigun Toxin A	800	small	1.6	200	500	300	0.375	16	187.5	105	31500
Toxigun Toxin B	900	small	1.8	300	700	400	0.4444↓	16	222.22	93.3	37333
Toxigun Toxin C	1000	small	2	400	900	500	0.5	16	250	84	42000
Anti-Alien Gas Heavy Missile	1200	small	2.4	280	700	420	0.35	15	175	70	29400
Anti-Alien Gas Mini Missile	1600	small	3.2	360	900	540	0.3375	30	168.75	52.5	28350
Anti-Alien Gas Grenade	1000	small	2	250	600	350	0.35	15	175	84	29400
Disruptor Armor - Head & Chest	3800	small	7.6	1500	3480	1980	0.5211↓	20	260.53	22.11	43768
Disruptor Armor - Arms & Legs	3400	small	6.8	1200	2830	1630	0.4794↓	20	239.71	24.71	42271
Disruptor Bomb Launcher	8000	large	8	3000	7000	4000	0.5	8	500	21	84000
Disruptor Inversion Bomb	4000	large	4	1500	3500	2000	0.5	25	500	42	84000
Stasis Bomb Launcher	6000	large	6	2000	4760	2760	0.46	10	460	28	77280
Stasis Field Bomb	2000	large	2	1200	2650	1450	0.725	20	725	84	121800
Disruptor Multi-Bomb Launcher	10000	large	10	4000	9260	5260	0.526	14	526	16.8	88368
Disruptor Multi-Bomb	5000	large	5	1800	4230	2430	0.486	30	486	33.6	81648
Light Disruptor Beam	12000	large	12	2000	5600	3600	0.3	5	300	14	50400
Medium Disruptor Beam	20000	large	20	4000	10500	6500	0.325	10	325	8.4	56400
Heavy Disruptor Beam	35000	large	35	8000	20500	12500	0.3571↓	15	357.14	4.8	60000
Small Disruption Shield	20000	large	20	5000	12500	7500	0.375	10	375	8.4	63000
Large Disruption Shield	30000	large	30	8000	19800	11800	0.3933↓	15	393.33	5.6	66080
Cloaking Field	35000	large	35	6000	16450	10450	0.2986↓	17	298.57	4.8	50160
Teleporter	45000	large	45	11000	27700	16700	0.3711↓	20	371.11	3.73	62347
Advanced Control System	15000	small	30	4000	8000	4000	0.2667↓	6	133.33	5.6	22400
Dimension Probe	25000	large	25	6000	10000	4000	0.16	2	160	6.72	26880
Bio-Trans	35000	large	35	12000	34000	22000	0.6286↓	2	628.57	4.8	105600
Explorer	55000	large	55	22000	44000	22000	0.4	2	400	3.05	67200
Retaliator	75000	large	75	35000	70000	35000	0.4667↓	2	466.67	2.24	78400
Annihilator	100000	large	100	50000	100000	50000	0.5	2	500	1.68	84000

¹ Based on listed Facility ie: Small will use 500, Large will use 1000 in the final calculations
² Not regarding time, salary, maintenance.
³ Rounding is only used for display only, all other calculations use the real number.
↓ Shortened to four decimal places.
† Quantity listed as decimal number = optimisation needed if not doing multi-week projects.

Conclusion

Optimisation

Every single skill point closer to the perfect 1000 total skill will decrease the time taken.

"Project Complete" screen only appears at the start of a new hour. If your project takes even one more minute into the new hour, you lose 59minutes because ..."start of a new hour"!
The best scenario would be to time a project so it finishes exactly on-a-new-hour when exact numbers are used in the calculation, but
Timing a project's end time when decimal numbers are included will give a very close approximation, so making it finish with no more than one minute before the hour allows some rounding errors.
If a small project can complete in one hour, the end-time will be at the end of this current hour irrelevant of when it was started (see above Build Time‡).

ad infinitum ad nauseam

Profits and all the calculations...

Start a project to last many days so that losing 1hour of time at the end becomes insignificant.

eg: losing 1hour of a 96hour total time production run is almost irrelevant, but losing 59minutes every 1hr+1min project run is unacceptable waste.

The amount of exotic items recovered on the battlescape will be much more profitable if you can manage to stop blowing things up for even just a second!! ...than trying to squeeze out the perfect production run. Its not an Accounting game.